Leases - Schedule of Supplemental Cash Flow and Other Information Related to Leases (Details) - USD ($) $ in Thousands	6 Months Ended
	Mar. 27, 2021	Mar. 28, 2020
Leases [Abstract]
Operating lease cost	$ 21,000	$ 19,300
Amortization of right-of-use assets	0	0
Interest on lease liabilities	0	0
Total finance lease cost	0	0
Short-term lease cost	2,100	1,700
Variable lease cost	4,900	3,500
Total lease cost	28,000	24,500
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	18,600	17,800
Operating cash flows from finance leases	0	0
Financing cash flows from finance leases	0	0
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	38,667	4,986
Finance leases	$ 0	$ 0